Combination of lidocaine gel and povidone-iodine to decrease acquired infections in procedures performed using topical anesthesia

Purpose: To test the antiseptic efficacy of povidone-iodine when mixed with topical lidocaine gel. Setting: Emory School of Medicine, Atlanta, Georgia, USA. Design: Experimental study. Methods: Staphylococcus epidermidis, Staphylococcus aureus, viridans streptococci (Streptococcus sanguinis), Escherichia coli, and Pseudomonas aeruginosa were grown on blood agar plates with povidone-iodine and/or lidocaine gel. The efficacy of sterilization was quantified by surviving bacterial colony-forming units. Results: Combination of povidone-iodine and lidocaine gel prevented bacterial growth to levels similar to povidone-iodine alone. Application of lidocaine gel to bacteria before povidone-iodine treatment allowed bacterial growth similar to controls not exposed to povidone-iodine. Conclusions: Povidone-iodine must be applied before lidocaine gel for effective antisepsis, but admixture of povidone-iodine with lidocaine gel was also effective and may reduce the risk of endophthalmitis associated with lidocaine gel use. This strategy offers a practice- changing alternative for preoperative prophylaxis in procedures requiring topical anesthesia. Copyright (C) 2020 Published by Wolters Kluwer on behalf of ASCRS and ESCRS.